A concern for future diesel fuels is the ability to produce higher quality and cleaner burning diesel fuels without extensive and expensive reprocessing. Cold flow properties of diesel oils, sometimes measured by the oil's cloud point, pour point, or cold filter plugging point, are aspects of fuel quality that may require seasonal adjustment. Traditionally, this issue is resolved through dewaxing, cracking, blend additives, or cutting the heavy tail out of the feed. Dewaxing may require substantial investment in an additional hydrotreating reactor or require addition of dewaxing catalyst in the hydrotreater bed, which sacrifices hydrotreating catalyst capacity of the hydrotreater.
There therefore remains a need for new methods and systems to efficiently dewax distillate feeds on a permanent or a seasonal basis.